President Donald Trump’s announcement on Thursday to withdraw the United States from participating in the Paris climate accord is not sitting well with many Boulder-area scientists who say the move will likely have many impacts on the U.S. and the rest of the world — none of them good.

“This is a step backwards,” said Mark Serreze, director of Boulder’s National Snow and Ice Data Center.

“Our nation should be playing a leadership role in trying to combat climate change,” he said. “The premise behind this decision that (the climate accord) is going to a job killer is just false. There is much more opportunity in green technology … That’s where the future lies.”

The Paris agreement was struck in 2015 to combat climate change, but Trump repeatedly mocked the agreement during his presidential campaign, saying that it would be detrimental to the U.S. economy. He said on Thursday that the United States will stick to the withdrawal process, which could take four years to complete.

Chris Bentley, of Boulder-based renewable energy-related company Independent Power Systems, said that he attended the Paris climate accord in 2015 and is disappointed by Trump’s announcement because he recalls walking away from the summit feeling good about the deal that had been made.

However, he said that the silver lining might come from more people being mobilized to get out and participate in combating climate change, because the work to stop the problem has to go on regardless of who is president.

“On one hand, I’m completely disappointed and sick to my stomach,” he said. “On the other hand, this is going to raise so much awareness.”

David Ciplet, an assistant professor of environmental studies at the University of Colorado Boulder, said Trump’s decision appears to come on the heels of years of efforts by the fossil fuel industry to undermine science on climate change in the pursuit of profits.

“Trump says he wants to drain the swamp,” Ciplet said. “It seems like what he is doing is business as usual, responding to corporate money and not people’s interests.”

He said that the decision comes as a major blow to smaller countries that don’t contribute much to overall carbon emissions but face inordinate consequences, because the climate accord affords them a seat at the table.

Ciplet, who is also co-director of the Just Transition Collaborative at CU — an organization that promotes social and environmental justice in the transition out of fossil fuels — added that climate change politics ultimately begin at the local level, and Boulder will have to be a leader.

“We need to be a leader nationally not just in mitigation, but on doing climate change policy that is socially just,” he said. “If we are going to create new green jobs, we need to ensure those are living wage jobs and accessible.”

Boulder Mayor Suzanne Jones said she is saddened and outraged by the “negative leadership on one of the most important issues facing our generation,” adding that the move by Trump “underscores the imperative of cities and local communities leading on this issue.”

“It’s important that we send a message to the rest of the world that just because President Trump isn’t going to lead, doesn’t mean that the United States isn’t going to do its part,” Jones said. “It’ll just be city by city rather than at the national level.”

Antonio J. Busalacchi, the president of the University Corporation for Atmospheric Research, issued a statement saying the United States’ withdrawal from the agreement creates “new uncertainties about the future of our climate.”

He continued that climate change poses major risks to food and water supplies, transportation systems and other resources worldwide, and rising temperatures and their impacts on weather patterns will endanger economic and military security.

Climate change consultant Joel Smith said it is unclear how serious an effect the withdrawal will have but it will clearly be negative. He called Trump’s announcement a “black day for addressing climate change.

“The U.S. did very well in negotiating the Paris agreement, and now we are going to turn away from it. That’s shameful,” Smith said. “I’m afraid it sends the message that you can’t rely on the Americans. One president might advance the ball, and another might pull us out.”

Serreze’s organization studies ice cover in the Arctic Ocean, and he said that it is on course to be seasonally ice-free within 40 years, which he said should serve as a red flag for the rest of the world with regard to the impact of climate change.

“I avoid cliches like the plague,” he said. “But this is the canary in the coal mine. … Climate change is here and it’s real and it’s going to get worse. To see a decision like this is disheartening.”

Staff Writer Alex Burness and The Associated Press contributed to this report.